16 Respiratory motion can affect the delivered dose distributionBackgroundRespiratory motion can affect the delivered dose distributionEspecially in the thorax/abdominal regionAvailable solutionsIncreased marginsMore dose will be delivered to the surrounding healthy tissueOrgans at risk must still be protected, which may be very difficult if they move near or into the desired target volumeGated treatmentDose delivery is synchronized with respiratory motionPotential for dose escalation, resulting in higher delivered dose to the tumor while healthy tissue is sparedThe correlation between internal and external (surrogate) motion must be known

23 The cRespiration conceptSimplicityNo markers to be placedIntegrated workflow through the whole processConfidenceNo additional doseSub-millimeter accuracy, measured at the same locations every fraction without manual guidanceParallel monitoring of thoraxic and abdominal breathingImmediate detection of irregular breathing or patient motionVersatilitySupport for several modes of operation – deep inspiration/end expiration breath hold, as well as coached and free breathingTight integration with CT and Linac equipment from major vendors